In Sudan, the Comprehensive Peace Agreement of 2005 left the Sudan People's Liberation Army (SPLA) intact, with responsibility for safeguarding security in the territory designated as South Sudan for a period of 6 years, after which the population would vote on secession. In essence, the SPLA was left to transform itself from a guerrilla army into a national armed force, with donor assistance. In early 2006, the SPLA and the South Sudan Ministry of SPLA Affairs launched a program for the transformation of the SPLA into a professional and operationally effective armed force. Four main transformation goals were earmarked by the SPLA leadership: (1) defining force structure, size, and accountability; (2) training SPLA soldiers and officers to enhance discipline, morale, and agility; (3) realigning SPLA roles and functions with the interim constitution of South Sudan, which involves civil-military relations; and (4) increasing the SPLA's lethality through rearmament and improvements in effectiveness and rapidity of response. In late 2006, a consortium of international donors from the United States, the United Kingdom, and Switzerland launched the Security Sector Development and Defense Transformation (SSDDT) program in Sudan. The transformation process has been in progress for 5 years, not long enough for a final assessment, but a reasonable period of time for an interim assessment of progress. How much progress has the transformation made toward each of its stated goals and why? The situation in South Sudan provides a unique opportunity to study military transformation in which an intact force and international donors are pursuing transformation/reform cooperatively, but with different emphases. The thesis draws largely upon primary sources to evaluate the extent of progress on each goal by the end of 2010, including unpublished government documents and the author's own experience as a direct participant in the process of transforming the SPLA since 2006.